Apparatus for stripping ingots from molds



May 17, 1938. E. GATHMANN APPARATUS FOR STRIPPING INGOTS FROM MOLDS 4Sheets-Sheet 1 Filed May 15, 1935 May 17, 1938. E. G'ATHMANN APPARATUSFOR STRIPFING INGOTS FROM MOLDS Filed May 15, 1935 4 Sheets-Sheet 2 y1938. E. GATHMANN APPARATUS FOR STRIPPING INGOTS FROM MOLDS 4Sheets-Sheet 5 Filed May 13, 1955 0 7 a 9 M4 0 4 %3 3 3 MW WWW Mm .ufi r7 1 H 1. 7% 8 7 6 9 5&4 3 5 4 u 3 M 3 III/IIIIIIII I n n as, g 7

Sum was,

May 17, 1938. E. GATHMANN APPARATUS FOR STRIPPING INGOTS FROM MOLDSFiled May 13, 1935 4 Sheets-Sheet 4 ?atented May 17, 1938 UNITED STATESPATENT OFFICE Emil Gathmann, Baltimore, Md., assignor to GathmannResearch Incorporated, Catonsville, Md., a corporation oi MarylandApplication May 13, 1935, Serial No. 21,246

11 Claims.

This invention relates to methods of and apparatus for stripping ingotsfrom molds and more particularly to methods of and apparatus forstripping ingots from big-end-up ingot molds,

such, for example, as molds of the type now well known in the art as theGathmann mold.

Heretofore several diiierent kinds of stripping apparatus have beenproposed and are fully disclosed in prior United States patents. Forexample, apparatus for stripping ingots irom big-endup molds of theGathmann type are disclosed in my prior Patents 1,059,667 and 1,059,668,both of April 22, 1913; 1,890,777, of December 13, 1932; 1,897,696, ofFebruary 14,1933; and 1,931,187, of

October 17, 1933. Apparatus for stripping ingots from big-end-down moldsare shown in numerous United States patents; for example, the patents toMorgan et 9.1. 656,416, of August 21, 1900;-

Taylor 788,339, of April 25, 1905; and Taylor 2 806,208, of December 5,1905. These latter patents disclose the type of stripper at present inuse in several large steel plants and known in the steel industry as theMorgan stripper.

. Up to and including the present time more ingots have been produced inbig-end-down molds than in big-end-up molds, but since better ingots canbe produced in big-end-up molds the use of such molds is increasingrapidly. In order to provide for the economical stripping of big-endupingots with a minimum of investment in new plant equipment, it has beenproposed to modify and adapt the present Morgan strippers for strippingbig-end-up molds. An adaptation of this type, suitable for use only instripping big-end-up 5 ingots cast with a sink head or hot top, isdisclosed in the C. L. Bigler et a1. Patent 1,807,275, of May 26, 1931,issued to the Morgan Engineering Company, of Alliance, Ohio, asassignee.

One object of the present invention is to pro- 40 vide an improvedstripping apparatus adapted for stripping ingots from big-end-up moldsregardless of whether the ingots be cast with or without shrink head orhot top portions.

Another object is to provide a stripping appa- 45 ratus comprising anovel adaptation and supplementing of the strippers now in use and knownas the Morgan stripper whereby the existing stripping mechanism, asadapted and supplemented by my invention, may be used for strippingingots 50 from big-end-up molds.

- A further object is to provide a stripping apparatus of the kindreferred to above in which the timing of certain of the parts is such asto assure safe operation.

55 Another object is to provide a mold stool and associatedstripper-operating means embodying improvements over the stool andstripper-operating means disclosed in the patent to McLaurin 1,963.30'7,of June 19, 1934,

A still further object is to provide an improved 5 method for strippingingots from big-end-up molds. a I

Other objects will become apparent from a 1 reading of the followingdescription, the appendpositions different from those occupied inFigures 1 and 2;

Figure 4 is a view similar to Figure 3 but with 25 certain parts showninstill diiferent positions;

Figure 5 is a view similar to Figures 3 and 4, the parts being shown instill diiierent positions;

Figure 6 is a top plan view of a mold stool assembly constructed inaccordance with the in- 30 vention and drawn on an enlarged scale;

Figure 7 is a detailed perspective view of an ingot stripping abutmentdrawn on an enlarged scale;

Figure 8 is a section on the line 8-8 of Figure 6; and

Figure 9 is a section on the line 9-9 of Figure 6.

The accompanying drawings illustrate a practical and the now preferredform of apparatus 40 embodying the invention as comprising overheadstripping apparatus generally designated A carried bya mobile bridge B;a big-end-up mold C; and a stool D carried by a car E and provided withstripping mechanism to be described hereinafter. An ingot F cast withouta shrink head or hot top portion is shown in the mold C, although itwill be understood that the apparatus may be employed for strippingingots from molds provided with shrink head portions.

The mold C is provided with a bottom opening I closed by means of aclosure device 2 terminating above the bottom of the opening i.

A stripping rod 3 is mounted with its head in the lower portion of themold bottom opening I mold directly on the stool with the mold bottomopening I in registration with the stool opening 4. The stool base isformed with a depression or recess generally designated 1 and comprisinga large rectangular central portion 8 and smaller end portions 9 whichextend respectively from the opposite ends of the central portion 8underneath the side guides 6. A pair of T-shaped strippinginstrumentalities or stripper rod abutments I0 is mountedfor slidingmovements in the stool recess I as shown most clearly in Figure 6, the

several vertical walls of the recess 8 providing guides for constrainingthe movement of the abutments ill to defined paths.

,When the mold is set up preparatory to' pouring, the abutments ID aremoved to their outer or full line positions as shown in Figure 6,whereby their heads will be disposed on opposite sides .of the stoolopening 4. The mold is then placed on the. stool with the bottom openingI inregistration with the stool opening 4, and the stripper rod 3 placedin the position shown in Figure 2, wherein the rod extends between theabutments l0 and down through the stool opening 4. In operation, afterthe ingot has solidified sufliciently to permit its being stripped, themold is raised in a manner later to be described, causing the strippingrod 3 to be lifted to a position above the plane of the tops of theabutments Ill, after which the abutments are moved in under thestripping rod and the mold then forced downwardly'while the stool isheld stationary. During such downward movement of the mold, the stripperrod will engage the abutments, which will block its further travel, sothat continued downward movement of the mold will effect relative upwardmovement of the stripping rod and ngot.

It is possible that, due to carelessness of workmen, the closure device2 may be seated imperfectly while the mold is "being set up preparatoryto teeming, and this may result in some leakage-of molten metal. Inorder to prevent any metal which leaks past the closure device fromrunning down between the abutments l0 and the associated guiding wallsof the stool recess 1, I

prefer to provide cover plates H secured on top of the stool base andextending across and covering the recess 8 and abutments III, with theexception of the extreme central portion of the stool, i. e., theportion directly above the stool opening 4. By employing these coverplates, any molten metal leaking through the mold bottom opening will beprevented from running into small clearancesbetween the abutments l0 andthe associated guiding walls of the'stool recess, it beingpo'ssible formolten metal to leak only into the relatively large open space at thecentral portion 8 of the recess 1 between the opposed adjacent faces ofthe abutments I0. It is obvious that any metal leaking into this openspace can easily be removed therefrom after it solidifies.

The mechanism for raising and lowering the mold and ingot to effect thestripping operation in the manner generally described above will now bedescribed.

The overhead stripping apparatus A includes a trolley or carriage l2mounted on rails l3 for travelling across the bridge B. An operator'scage l4 provided with suitable controls for motors and winding drums orother similar mechanism mounted on the carriage depends from thecarriage and is so positioned as to enable an operator in the cagereadily to observe the positions and movements of the mold, ingot, andassociated Secured inside of the sleeve iii are bushings l8 which arerotatable with the sleeve and which are provided with square centralopenings receiving for sliding movements the square upper portion I9 ofa staff generally designated 20, the arrangement being such thatrotation of the worm wheel I! willeffect simultaneous rotation of thesleeve l6 and the stafi 20, while at the same time the staff 20 may bemoved-vertically with respect to the sleeve and worm wheel by meanslater to be described. A tube 2! is connected to the top of the sleevel6 and closed at its top in order to prevent dust from entering inbetween the sleeve l6 and stafl. 20. r I

.The lower end of the staff is formed or provided with mutually reversedthreads 22 and 23 engaging respectively with travelling sleeves or nuts24 and 25. The lower nut 25 is secured within a sleeve 26, which, at itslower end, has threaded connection with a stem 21 the purpose of whichwill be referred to later. The upper nut 24 engages under a shoulder 28on an outer sleeve 29 which surrounds and is slidable with respect tothe sleeve 26 previously referred to. In operation, rotation of thestaff 20 will, by virtueof the reverse direction of the threads 22 and23, cause the nuts 24 and 25 and consequently the respectively connectedsleeves 29 and 26 to move in opposite directions. The parts'of theoverhead stripping apparatus A thus far described are substantially thesame as those employed in the well known Morgan stripper as shownforexample in the patents previously referred to, and per se do notconstitute the present invention.

As previously stated, one feature of the present invention resides in'its adaptability to the plants. In order to modify and augment and thusadapt the Morgan stripper for the stripping of big-end-updngots casteither with or without shrink head portions, I preferably provide a moldpushing yoke 30 pivotally connected to the stem 21 as at 3|, the spacedlegs of the yoke being adapted to engage the top of the mold C onopposite sides of the latter so as to push the mold positivelydownwards. the molds to be stripped difier in size, the yoke maycomprise means for adjusting the legs later-- ally' with respect to eachother, for example, as

shown in my prior Patent 1,931,187 of October 17, 1933. For lifting themold, I have provided a pair of bails 32 pivotally connected to the yokein order to enable the latter to be moved directly For use in plantswhere 4 iii) under the yoke 30, or, conversely, if desired, to move theyoke over the mold. For moving the bails to the desired positions, Iprovide suitable drums or winding mechanism on the carriage l2 asindicated in dotted lines in Figure 2, and con trol mechanism located inthe operator's cage by means of which cables 36 connected to the ballsmay be raised or lowered so as to position the bails in their outerposition or allow them to drop by gravity to mold-engaging position asindicated in Figure 3. It will be understood that, after the mold hasbeen positioned directly under the yoke 3|! as shown in Figure 2, thestat! 2|] will ,be rotated to lower the yoke 30, after which the cables35 are slackened in order to permit the bails to move inwardly bygravity, bringing the gripping portions 3| of the bail intomold-engaging position underneath the lugs 35 on the mold. The partsthen are ready to effect lifting of the mold and ingot to the positionshown in Figure 4.

As previously stated, after the mold has been raised, the abutments IIIare moved in under the stripper rod and the mold pushed down, bringingthe lower end of the stripping rod into engagement with the abutments.In order to provide an inflexible driving connection and also to preventany of the stripping pressure from being exerted on the car E, I providemeans connected to the sleeve 29 and adapted to engage and hold thestool against downward movement. An important feature of the inventionresides in the provision of stool-holding means so constructed,arranged, and timed with respect to movements of the other parts of theapparatus as to move the stripping abutments it into their inner orblocking positions substantially simultaneously with movement of thestool-holding means into stoolhoiding position, By virtue of thisarrangement. it is not possible to exert stripping pressure until afterstool-holding means has been moved to stool-holding position. In theembodiment shown, the stool-holding means comprises a pair of bifurcatedarms 3i pivoted as at 38 to wings 39 integral with the sleeve support29, the lower ends of arms 31 being formed with gripping orstool-holding portions to adapted to engage the lower faces of lugs llon the stool. Because of the pivoted connection of the ai'msat 3B, thearms are adapted to be swung to an outer position as shown in Figures 1and 2, or to an inner stoolholding position as shown in Figures 3, 4,and 5. For efiecting such swinging movements to these two positions, thearms 3i are provided with upper extensions 42 pivotally connected tolinks 53 which in turn are pivotally connected to hell cranks 5 mountedon pintles 5 carried by the wings as on the sieeve 29. Cables 4% areconnected to the bell cranks M outside of the pinties t5, and cables 5!are connected to the bell cranks inside of the pintles 15. In order toswingthe arms 3'2 ontwardiy to the positions shown in Figures i and 2,the inner cables 11 are drawn up by means of the drums on the carriagel2, and the outer cables let down from the drums. Conversely, when it isdesired to swing the arms inwardly, the outer cables 48 are drawn up andthe inner cables 41 let down. All these operations of course are underthe control of the operator located in the cage 13.

The stool-holding portions ll of the arms 31 are mi-de suilicientlylarge or are extended downwardly so as to be adapted to enga e the outerprojecting ends of the abutments II when the arms 3'! are movedinwardly. In operation, asearning the par s to he in the positions shownin Figure 3, the stall 20 is rotated in a direction .to cause the nut25, the sleeve 26, the yoke 30, and the bails 32 to be raised, therebymoving the mold to the position shown in Figura Simultaneously with suchmovement of the mold, the nut 2|, sleeve 29, and arms 31 will movedownwardly,

bringing the arms to the positions shown in dotted lines in Figure 4.Thereafter the cables 46 and 41 will be manipulated to move the arms 31inwardly to bring the gripping or stool-holding portions 40 under thestool lugs 4|. While moving to this position, the stool-holding portions40 will engage the abutments l0 arid move them to the positions shown inFigure 4, wherein their inner ends will lie under the stripping rod 3.

a After the parts have been moved to the positions shown in full linesin Figure 4, the stall 20 will be rotated in reverse direction, causingthe nut 24 to move upwardly and the nut 25 to move downwardly, and inconsequence the yoke 30 will be moved positively downwards and the arms31 will be moved upwardly. Thus there are effected relative upwardmovement of the stool, the abutments ill, the stripping rod 3, andtheingot F, and relative downward movement of the mold C, whereby the ingotwill be stripped and moved to the position shown in Figure 5. Thereafterthe staff 28 will again be reversed and rotated until the stool and moldare deposited upon the car E, after which the bails 32 and the arms Ellare moved to their outer inoperative positions as shown in Figure 2. Thecar and supported mold and ingot may then be moved to a position nearthe soaking pit and the ingot withdrawn from the mo d by tongs or thelike.

It is apparent that by my invention strippers of the Morgan type now inuse for stripping bigsure can be exerted, whereby there will he nodanger of applying stripping force to the mold car. Although theapparatus and method disclosed by way of example embody the inventionregardless of in a practical and the at present preferred manner,changes may be made without departing from the invention as defined inthe claims.

I claim:

1. Apparatus for partially stripping an ingot from a big-end-up moldhaving a bottom opening and supported on a stool comprising means forpositively moving the mold in two mutually ODDOS te directions; astripper rod mounted in said bottom opening; a stripper rod abutmentmounted on said stool for movements into and out of cooperative positionrelative to said stripper rod; and means including a stool-engaging andholding member and a support for mounting said stool-engaging member incooperative position relative to said mold moving means and for movementinto stool-engaging and holding posi: tion and out of stool-engaging andholding posi, tion, said stool-engaging and holding means being adapted,when moved to stool-engaging and holding position, to engage saidabutment and move it into said cooperative position.

2. In apparatus for partially stripping ingots from molds, thecombine-firm of a mold stool; means for positively moving the mold intwo mutually opposed directions; movable means for stool-holding meansadjacent to the stool; and stripping means including an abutment mountedon said stool for sliding movements substantially perpendicular to thedirection of stripping frominoperative position to operative strippingposition in response to movement of said holding means.

3. Apparatus for partially stripping an ingot from a big-end-up moldhaving a bottom opening and supported on a stool, said apparatuscomprising a stripper rod mounted in said bottom opening; a pair ofstripper rod abutments movably mounted on said stool and normallypositioned on opposite sides of said stripper rod; means for lifting andlowering the mold; and stool-holding means comprising a pair of liftingarms mounted for movements to stool-engaging position and adapted whenso moved simultaneously to engage said abutments and move the latterunder said stripper rod, and a support for mounting said lifting arms incooperative positioris relative to the mold lifting and lowering means.

4. In apparatus for partially stripping ingots from ingot molds, a moldstool assembly comprising a, stool proper formed with a horizontalguideway T'-shaped in plan; and an abutment also T-shaped in plan andslidable in said guideway, said abutment having an extension projectingoutwardly through and beyond an outer face of said stool.

5. In apparatus for partially stripping ingots from ingot molds, a moldstool assembly comprising a stool proper having a base and a side andformed with a horizontal guideway extending in said base and throughsaid side; an abutment slidably mounted in said guideway; and a coverfor a portion of said guideway and abutment adjacent to said stool side.

6. In apparatus for partially stripping ingots from ingot molds, a moldstool assembly comprising a stool proper having a base and oppositelydisposed sides, and being formed with horimold downwardly, a pair ofmold-lifting bails piv-- zontal guideways extending in said base andthrough said sides; a pair of abutments mounted in the respectiveguideways for sliding movements towards and from the center of thestool;

and covering means carried by said stool and.v

disposed above portions of said guideways and abutments adjacent to saidstool sides.

7. In apparatus for partially stripping ingots from ingot molds, a moldlifting and lowering mechanism including a yoke adapted to push the molddownwardly; a pair of mold-lifting bails pivotally connected to theyoke; means for raising and lowering said 'yoke together with saidbails; and means for swinging said bails about their pivots on saidyoke.

8.In apparatus for partially stripping ingots from ingot molds, a moldlifting and lowering mechanism including a yoke adapted to push theotally suspended from the yoke, means for raising and out ofstool-engaging position, means forv moving said arms into and out ofmold-engaging position, a support upon which the vertically movablemeans are carried, and means for raising and lowering said verticallymovable means.

9. Apparatus for partially stripping an ingot from a big-ehd-up moldhaving a bottom opening and supported on a stool comprising a stripperrod mounted in said bottom opening; a stripper rod abutment carried bysaid stool and normally positioned in inoperative position at one sideof said stripper rod; a mold lifting and lowering mechanism including ayoke adapted to push the mold downwardly, a pair of mold-lifting bailspivotally suspended from the yoke, means for raising and lowering sa-idyoke together with said bails, and means for swinging said bails abouttheir pivots on said yoke; and a stool holding mechanism supportedadjacent to said mold lifting and lowering mechanism and comprising apair of stool-engaging arms,' vertically movable means upon which saidarms are mounted for.

movable means, one of said arms being adapted when moved tostool-holding position to engage said abutment and move it under saidstripper rod. v

10. In apparatus for partially stripping an ingot from a big-end-upmoldsupported on a stool, means for pushing the mold downwardly; meanssupported adjacent to said stool and movable from inoperative positioninto operative position in engagement with the stool for holding thelatter against downward movement; and stripping means including anabutment shiftable from inoperative position to operative strippingposition in response to such movement of said stoolholding means forblocking downward movement of the ingot.

11. In apparatus for partially stripping an ingot from a mold, thecombination of a mold stool; means for positively moving the mold in twomutually opposed directions; stool-holding means mounted for movementsinto and out of stoolholding position; andstripping means'including anabutment carried by the stool and being movable from inoperativeposition to operative stripping position with respect to both the moldand stool simultaneously in response to movement of do

